# Intuitive reasoning on the nature of time

I claim that the measurement of time is the measurement of change if the following holds:

• Our universe is (or can be represented as) a simulation, namely a set of data operated on by an algorithm. The algorithm operates on and changes the data.
• Observations made within our universe are not affected by how quickly the universe is being simulated in the outside world.
• In particular, the simulation is not affected in any way by the outside world. The algorithm changes the data according only to its current state, and does not take any external input.

The reasoning is as follows:

If the universe is a simulation, is there a way to make it “lag”? That is, to slow down the computer that is simulating our universe? Will it lag if we detonate millions of atomic bombs, forcing it to calculate large amounts of complex physics?

Assuming that there is a way to make it “lag”, the more important question is whether we are able to observe this lag in the universe.

A program running on a computer can measure how quickly the computer is running by accessing the computer’s “clock”, which gives it the current time. A program running on a computer that lacks a “clock” (or does not provide the program any way to access it) cannot know how quickly the computer is running, and more importantly, is not affected by how quickly the computer is running. It therefore cannot observe whether the computer is lagging.

The intuitive idea is to think of our universe as such a computer program. That is, one that does not take any input of time from the outside world and is not affected by it. So even if detonating millions of atomic bombs slows down the simulation speed of the universe, we would never be able to observe this slowdown. Instead, we will simply observe a consistent demonstration of the laws of physics.

Therefore the simulated universe does not depend on time, and yet time can be observed from within the universe. The simulation of our universe does not depend on time, so how did time appear out of nowhere?

We observe that pausing and resuming the simulation does not affect the observation of time from within the universe (i.e. we wouldn’t notice if the universe was paused for a moment in the outside world). Therefore the time observed within the simulation depends only on the data within the simulation. A change in time must therefore mean a change in the data inside the simulation.

More rigorously, we can define the simulation algorithm as one that does not depend on anything other than its current state - it does not take and is not affected by any external input and therefore does not depend on the time of the outside world.

I claim that if the above holds, then as a consequence, any physics equation containing time is in fact a parameterized version of a more complete equation where “time” is replaced by one or more measurable quantities.

My questions are:

• Does this idea resolve any of the issues that we currently have?
• How would it conflict with what we already know?
• In particular, does it relate to the conservation of mass or special relativity?
• Is the second claim valid? If possible, please provide an example.
• What other similar ideas are there?
• What should I learn to go about a more formal presentation of my argument?

Please let me know if there is a more suitable place to share this idea. Thank you for your time.

• Your argument puts me in mind of 'A bunch of rocks' ep of XKCD xkcd.com/505 You need to have a 'timeless' reference frame, & a way to build up 'now'. See 'Is there such thing as the present?' philosophy.stackexchange.com/a/56621/30474 Interaction is definitely key. Rather than independent entities, we should focus on the 'surface' between them, of interactions. If time is an emergent dimension (Noether's theorem), we can see conservation of information + many worlds, as the 4th D curving in a 5th D. The holographic principle deals with similar partial dimensions, also AdS-CFT Jun 8, 2021 at 18:18

Time as an internal sequence of changes was conceived by philosophers such as Leibniz long ago before any world simulation hypothesis according to reference here:

But time, like space, is an illusion. How then is one to understand change without time? The important question is: what conception of time is being discussed? Just like space, Leibniz is objecting to any conception of time which is exterior to the objects that are normally said to be “in” time (time as an exterior framework, a dimension). Also, he objects to time as mere chronology, a conception of time as a sequence of “now points” that are ideally separable from one another (that is, not essentially continuous) and are countable and orderable separately from any thing being “in” them (that is, abstract).

And in contemporary loop quantum gravity theory, Rovelli also proposed similar ideas as referenced here:

According to theoretical physicist Carlo Rovelli, time is an illusion: our naive perception of its flow doesn’t correspond to physical reality. Indeed, as Rovelli argues in The Order of Time, much more is illusory, including Isaac Newton’s picture of a universally ticking clock. Even Albert Einstein’s relativistic space-time — an elastic manifold that contorts so that local times differ depending on one’s relative speed or proximity to a mass — is just an effective simplification.

So what does Rovelli think is really going on? He posits that reality is just a complex network of events onto which we project sequences of past, present and future. The whole Universe obeys the laws of quantum mechanics and thermodynamics, out of which time emerges... Rovelli is one of the creators and champions of loop quantum gravity theory, one of several ongoing attempts to marry quantum mechanics with general relativity... Alongside and inspired by his work in quantum gravity, Rovelli puts forward the idea of ‘physics without time’. This stems from the fact that some equations of quantum gravity (such as the Wheeler–DeWitt equation, which assigns quantum states to the Universe) can be written without any reference to time at all.

As Rovelli explains, the apparent existence of time — in our perceptions and in physical descriptions, written in the mathematical languages of Newton, Einstein and Erwin Schrödinger — comes not from knowledge, but from ignorance. ‘Forward in time’ is the direction in which entropy increases, and in which we gain information.

So in summary entropy (information) may be a better measurable quantity than time. In ancient times Confucius once said “If a man in the morning hear the right way (the Tao), he may die in the evening without regret." as referenced here, so seems time replacement is not a new or radical idea...